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Toward eradication: the effect of Mycobacterium bovis infection in wildlife on the evolution and future direction of bovine tuberculosis management in New Zealand.

Livingstone PG, Hancox N, Nugent G, de Lisle GW - N Z Vet J (2015)

Bottom Line: New Zealand's bovine tuberculosis (TB) control programme has greatly reduced the burden of tuberculosis on the farming industry, from 11% of mature cattle found with TB at slaughter in 1905 to <0.003% in 2012/13.The adoption of coordinated national pest management strategies, with increasingly ambitious objectives agreed between government and industry funders, has driven a costly but very successful management regime targeted at controlling TB in the possum maintenance host.This success has led to initiation of a strategy designed to eradicate TB from New Zealand's livestock and wildlife, which is considered a realistic long-term prospect.

View Article: PubMed Central - PubMed

Affiliation: a TBfree New Zealand , PO Box 3412, Wellington 6140 , New Zealand.

ABSTRACT
New Zealand's bovine tuberculosis (TB) control programme has greatly reduced the burden of tuberculosis on the farming industry, from 11% of mature cattle found with TB at slaughter in 1905 to <0.003% in 2012/13. New Zealand implemented TB control measures in cattle from the mid-twentieth century, and later in farmed deer. Control was based on established methods of tuberculin testing of herds, slaughter of suspect cases, and livestock movement control. Unexplained regional control failures and serious disease outbreaks were eventually linked to wildlife-vectored infection from the introduced Australian brushtail possum (Trichosurus vulpecula), which also triggered a wildlife disease complex involving a range of introduced species. This paper reviews the progressive elucidation of the epidemiology of Mycobacterium bovis in New Zealand's wildlife and farmed livestock, and the parallel development of research-led, multi-faceted TB control strategies required to protect New Zealand's livestock industries from damaging infection levels. The adoption of coordinated national pest management strategies, with increasingly ambitious objectives agreed between government and industry funders, has driven a costly but very successful management regime targeted at controlling TB in the possum maintenance host. This success has led to initiation of a strategy designed to eradicate TB from New Zealand's livestock and wildlife, which is considered a realistic long-term prospect.

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Related in: MedlinePlus

Boundary locations of areas in which tuberculosis (TB) was identified, or was strongly suspected to be present, in possums in New Zealand, showing the maximum size of the areas during 1980 (dark blue), 1994 (green), 2005 (sky blue), and the additional area identified in 2012 (orange). A number of the areas were subsequently declared free of TB or their size was reduced following the eradication of TB from the possum population. These changes are not shown on the map. This Figure uses the 1980 boundary from Figure 3 and then uses additional information compiled by PG Livingstone to define the boundaries for 1994, 2005 and 2012, based on GIS mapping.
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Figure 0004: Boundary locations of areas in which tuberculosis (TB) was identified, or was strongly suspected to be present, in possums in New Zealand, showing the maximum size of the areas during 1980 (dark blue), 1994 (green), 2005 (sky blue), and the additional area identified in 2012 (orange). A number of the areas were subsequently declared free of TB or their size was reduced following the eradication of TB from the possum population. These changes are not shown on the map. This Figure uses the 1980 boundary from Figure 3 and then uses additional information compiled by PG Livingstone to define the boundaries for 1994, 2005 and 2012, based on GIS mapping.

Mentions: The increasing number of locations at which TB was found in possums indicated that infection was spreading within the wildlife population through extensive, rugged and forested terrain as displayed in Figures 3 and 4. Tuberculous possums then became a source of infection for cattle at these new locations. While most juvenile possums remain within 2 km of their natal home range, between 20% and 30% disperse up to 5 km, and there is a record of a juvenile migrating 41 km from its natal site (Cowan and Clout 2000; Cowan 2001). Although most dispersal is by juveniles, adults also sometimes shift home ranges. Tuberculosis was therefore likely to have been transferred from one location to another through a series of migrations by infected possums (Pfeiffer et al. 1995), whereby infected migrants have established infection in a new local possum population, which then triggered further waves of expanding infection. Additionally, or alternatively, infection may also have been spread through a series of spillover-spillback transmission events involving possums, wild deer, feral pigs and then back to possums as shown in Figure 2.Figure 3.


Toward eradication: the effect of Mycobacterium bovis infection in wildlife on the evolution and future direction of bovine tuberculosis management in New Zealand.

Livingstone PG, Hancox N, Nugent G, de Lisle GW - N Z Vet J (2015)

Boundary locations of areas in which tuberculosis (TB) was identified, or was strongly suspected to be present, in possums in New Zealand, showing the maximum size of the areas during 1980 (dark blue), 1994 (green), 2005 (sky blue), and the additional area identified in 2012 (orange). A number of the areas were subsequently declared free of TB or their size was reduced following the eradication of TB from the possum population. These changes are not shown on the map. This Figure uses the 1980 boundary from Figure 3 and then uses additional information compiled by PG Livingstone to define the boundaries for 1994, 2005 and 2012, based on GIS mapping.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4566898&req=5

Figure 0004: Boundary locations of areas in which tuberculosis (TB) was identified, or was strongly suspected to be present, in possums in New Zealand, showing the maximum size of the areas during 1980 (dark blue), 1994 (green), 2005 (sky blue), and the additional area identified in 2012 (orange). A number of the areas were subsequently declared free of TB or their size was reduced following the eradication of TB from the possum population. These changes are not shown on the map. This Figure uses the 1980 boundary from Figure 3 and then uses additional information compiled by PG Livingstone to define the boundaries for 1994, 2005 and 2012, based on GIS mapping.
Mentions: The increasing number of locations at which TB was found in possums indicated that infection was spreading within the wildlife population through extensive, rugged and forested terrain as displayed in Figures 3 and 4. Tuberculous possums then became a source of infection for cattle at these new locations. While most juvenile possums remain within 2 km of their natal home range, between 20% and 30% disperse up to 5 km, and there is a record of a juvenile migrating 41 km from its natal site (Cowan and Clout 2000; Cowan 2001). Although most dispersal is by juveniles, adults also sometimes shift home ranges. Tuberculosis was therefore likely to have been transferred from one location to another through a series of migrations by infected possums (Pfeiffer et al. 1995), whereby infected migrants have established infection in a new local possum population, which then triggered further waves of expanding infection. Additionally, or alternatively, infection may also have been spread through a series of spillover-spillback transmission events involving possums, wild deer, feral pigs and then back to possums as shown in Figure 2.Figure 3.

Bottom Line: New Zealand's bovine tuberculosis (TB) control programme has greatly reduced the burden of tuberculosis on the farming industry, from 11% of mature cattle found with TB at slaughter in 1905 to <0.003% in 2012/13.The adoption of coordinated national pest management strategies, with increasingly ambitious objectives agreed between government and industry funders, has driven a costly but very successful management regime targeted at controlling TB in the possum maintenance host.This success has led to initiation of a strategy designed to eradicate TB from New Zealand's livestock and wildlife, which is considered a realistic long-term prospect.

View Article: PubMed Central - PubMed

Affiliation: a TBfree New Zealand , PO Box 3412, Wellington 6140 , New Zealand.

ABSTRACT
New Zealand's bovine tuberculosis (TB) control programme has greatly reduced the burden of tuberculosis on the farming industry, from 11% of mature cattle found with TB at slaughter in 1905 to <0.003% in 2012/13. New Zealand implemented TB control measures in cattle from the mid-twentieth century, and later in farmed deer. Control was based on established methods of tuberculin testing of herds, slaughter of suspect cases, and livestock movement control. Unexplained regional control failures and serious disease outbreaks were eventually linked to wildlife-vectored infection from the introduced Australian brushtail possum (Trichosurus vulpecula), which also triggered a wildlife disease complex involving a range of introduced species. This paper reviews the progressive elucidation of the epidemiology of Mycobacterium bovis in New Zealand's wildlife and farmed livestock, and the parallel development of research-led, multi-faceted TB control strategies required to protect New Zealand's livestock industries from damaging infection levels. The adoption of coordinated national pest management strategies, with increasingly ambitious objectives agreed between government and industry funders, has driven a costly but very successful management regime targeted at controlling TB in the possum maintenance host. This success has led to initiation of a strategy designed to eradicate TB from New Zealand's livestock and wildlife, which is considered a realistic long-term prospect.

Show MeSH
Related in: MedlinePlus